What Keeps Us in Balance?

How Input From Muscles and Joints Affects Our Balance

Just as a baby first learns how to balance by practicing and repeating certain movements, each of us adjusts to changing environments or health conditions throughout our lives to keep our balance. But how do our muscles and joints play into this?

Balance Maintained by Our Complex Sensorimotor Control Systems

Our balance is maintained by complex sensorimotor control systems all working together, and if one of these systems is upset or not working properly, we can lose balance. The three main systems of the body that provide sensory information to keep us in balance are vision, the vestibular system (inner ear) and the proprioceptive (or somatosensory) system.

It is the proprioceptive system that involves feedback to our brains from our muscles, joints and pressure sensors. This system has pressure and position sensors in the feet, trunk and spine. According to the Vestibular Disorders Association (VEDA), sensory information coming from our necks and ankles are the most important. "Proprioceptive clues from the neck indicate the neck indicate the direction in which the head is turned. Cues from the ankles indicate the body’s movement or sway relative to both the standing surface (floor or ground) and the quality of that surface (for example, hard, soft, slippery, or uneven).”

Information from muscles, joints and skin is produced from sensory receptors that react to pressure or stretching in tissues surrounding it in the body, telling our brains about our position in space.

How Does Motor Output Back to Our Muscles and Joints Affect Balance?

If we start tipping forward for example, the brain senses increased pressure in the front of the soles of our feet and our ankles bending.  The brain can then send instructions to the muscles along back of our body to keep us from tipping further forward and pull us back upright if we weren’t leaning forward on purpose.  The other two balance systems should help out with this reaction as well: the eyes should notice the forward sway relative to one’s surroundings and the inner ears should sense the forward tilt as well.

If one or more of these three systems is not working well, then the brain’s instructions to these antigravity muscles can be delayed or inaccurate, resulting in unsteadiness. Vestibular rehabilitation and balance training can help a person learn to compensate and improve their balance reactions by utilizing the remaining systems more effectively.

Contact us to find a vestibular therapist near you.

How Vestibular Rehabilitation Therapy Can Help With Ménière’s Disease

What Are the Symptoms of Ménière’s Disease?

Some people who are thought to have Ménière's Disease actually have a form of Migraine

According to the Vestibular Disorders Association (VEDA), symptoms of a Ménière’s Disease attack can vary between individuals as well as between different progressive stages of the attack as it occurs. Some people have a bit of a warning that an attack is coming, including dizziness, lightheadedness, unsteadiness and hearing change. However, as the attack gets going in earnest, there is typically ear fullness, ringing/roaring or loss of hearing, and spontaneous, violent vertigo, usually lasting for hours.

It should also be mentioned that some people who are thought to have Ménière’s Disease actually turn out to have a form of Migraine. Many of the symptoms can be very similar, hence the occasional misdiagnosis, and Migraine is far more prevalent than Ménière’s. You do not necessarily have to have a headache for it to be Vestibular Migraine but if you do have a headache or head pressure with your attacks, or notice disturbance to your visual field / sensitivity to visual stimuli like light or motion before your attacks, be sure to let your Family Doctor and Ear, Nose & Throat Doctor know.

What Causes Ménière’s Disease?

Although the exact cause is unknown, it is generally accepted that the symptoms result from what's called endolymphatic hydrops or "increased pressure of an abnormally large amount of endolymph [the fluid that fills the balance organ in our inner ears] in the inner ear and/or from the presence of potassium in an area of the inner ear where it doesn't belong." (VEDA).

Some of the theories proposed regarding the cause of Ménière’s Disease include an autoimmune reaction, a genetic connection, circulation problems, migraine, and a viral infection. Most of the adults who have Ménière’s Disease are between 40 and 60 years of age.

How Vestibular Rehab Can Help Those with Ménière’s Disease

Unfortunately, there is no "cure" for Ménière’s Disease. Some people with Ménière’s Disease return to feeling 100% between attacks, other than typically a progressive hearing loss. For those people, the role of the Vestibular Therapist is purely educational and Vestibular Rehabilitation is not needed. We can help the sufferer understand more about the condition and some dietary and lifestyle changes they might be able to try in order to reduce the frequency of the attacks.

For others, especially after repeated attacks, the function of the vestibular part of the inner ear does NOT bounce back to normal between attacks, and those people have ongoing symptoms. In addition to the education mentioned above, for these people we would provide a thorough assessment to identify what vestibular problems are persisting, then choose from the following vestibular rehabilitation techniques to help minimize their symptoms:

• Adaptation or gaze stabilization training to help with being able to focus clearly with head movement;
• Habituation techniques to reduce dizziness or sensitivity to movement;
• Static and dynamic balance training to reduce unsteadiness;
• Repositioning Maneuvers if a condition called BPPV has gotten triggered by the attack;
• Manual therapy on the neck to reduce the muscle tension and guarding of head movement that often follows an attack.

These techniques do not cure or prevent attacks, but can help people feel much better between attacks.

Contact us at http://www.lifemarkvestibular.ca - we can help!

Not All Vestibular Dizziness is from the Inner Ear

Problems Can Result from Central Vestibular Connections Within the Brain

The ears are for more than just hearing.  There is what’s called a vestibular apparatus in the inner ear that is for sensing our head positions and movements.  While problems with this part of the inner ear is a common source of dizziness, sometimes the vestibular problem is not because of the ear(s) at all but rather the central vestibular connections within the brain.

Inner Ear Information Sent to Processing Centers in the Brain in a Fraction of a Second

The vestibular part of the inner ear is just one piece of a whole vestibular system, and problems anywhere along the nerve pathways in this system can cause dizziness or balance problems.  Here’s how the system works:  The inner ears send their information about head movement/position in along nerves to the main vestibular processing centers in the brain called the vestibular nuclei.  With help from other parts of the brain, in particular the coordination center or cerebellum, the vestibular nuclei weigh out the information from the ears against each other, as well as against what your eyes are seeing and your body is feeling, in order to be really sure about what body position or movement is going on.  Once it has that figured out, the nuclei send instructions:

1. up to your eye muscles to tell the eyes how to move so that we can keep things in focus while the head is moving, and 
2. down your spinal cord to all the muscles that need to fire in order to keep us upright and balanced.

This all happens in a fraction of a second!  The vestibular reflexes are among the fastest in the body since, as you can imagine, being able to see clearly when moving and keeping one’s balance are so important for function and survival. 

The Vestibular System Involves Many Nerve Pathways & Many Parts of the Brain and Body

So as you can see, the vestibular system is a very complex one, involving many nerve pathways and many parts of the brain and body.  That being the case, there are lots of potential trouble spots that have nothing to do with the inner ears but are still vestibular-related.   The inner ear is the most common culprit when it comes to vestibular dizziness, however, some conditions that can affect the central vestibular pathways and connections within the brain include:

• Migraine
• Tumors
• Head Injury
• Multiple Sclerosis
• Vestibular Epilepsy
• Stroke
• Age or disease-related degeneration of brain tissue
• Or anything impairing the supply of blood, oxygen or glucose to parts of the brain

While we can often make some positive changes with Vestibular Rehabilitation for people with central (brain-related) vestibular problems, it often takes longer, and the outcomes are not as good as when the problem is with the inner ear.  However, people with only central vestibular issues have better outcomes than those with both central and ear-related problems.

Contact us at http://www.lifemarkvestibular.ca - we can help!